Since I don't read those languages, I'll ask: is the fundamental treatment of miles/points by the German, Austrian, or other governments actually different in practice? Do airlines send people the equivalent of a US 1099 every year for the miles they've "earned" (I put that word in quotes, because the more accurate term is purchased). Are employers somehow responsible for withholding based on how many miles they guess an employee might have received from some travel company?

The reason I ask about actual practice (as opposed to theory) is that even in the U.S., the IRS didn't exactly issue an ironclad statement defining miles as holding zero value. They just, at some point a few years ago, said "we'll stay out of it." Perhaps to avoid the many knock-on effects that would negatively affect everyone involved...as I've posted before, I believe that defining miles as holding value in the eyes of the IRS would lead to many unintended consequences that, while done with "consumer protection" intent, would ultimately end the programs as we know them.